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The Respiratory System in Babies

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What is respiration?

Respiration is the act of breathing in and out. When you inhale, you take in oxygen. When you exhale, you give off carbon dioxide.

What makes up the respiratory system?

The respiratory system is made up of the organs involved in the interchanges of gases. It consists of the:

Nose

Mouth (oral cavity)

Throat (pharynx)

Voice box (larynx)

Windpipe (trachea)

Airways (bronchi)

Lungs

The upper respiratory tract includes the:

Nose

Nasal cavity

Sinuses

The lower respiratory tract includes the:

Voice box (larynx)

Windpipe (trachea)

Lungs

Airways (bronchi and bronchioles)

Air sacs (alveoli)

What is the function of the lungs?

The lungs take in oxygen, which the body's cells need to live and carry out their normal functions. They also get rid of carbon dioxide. This is a waste product of the cells.

The lungs are a pair of cone-shaped organs made up of spongy, pinkish-gray tissue. They take up most of the space in the chest, or the thorax (the part of the body between the base of the neck and diaphragm). They are enveloped in a membrane called the pleura.

The lungs are separated from each other by the mediastinum, an area that contains the following:

Heart and its large vessels

Windpipe (trachea)

Esophagus

Thymus gland

Lymph nodes

The right lung has 3 lobes. The left lung has 2 lobes. When you breathe, the air:

Enters the body through the nose or the mouth

Travels down the throat through the voice box (larynx) and windpipe

Goes into the lungs through tubes called mainstem bronchi:

One mainstem bronchus leads to the right lung and one to the left lung

In the lungs, the mainstem bronchi divide into smaller bronchi

Then into even smaller tubes called bronchioles

Bronchioles end in tiny air sacs called alveoli

Breathing in babies

An important part of lung development in babies is the production of surfactant. This is a substance made by the cells in the small airways. It consists of phospholipids and protein. By about 35 weeks gestation, most babies have developed enough surfactant. Surfactant is normally released into the lung tissues where it helps lower surface tension in the airways. This helps keep the lung alveoli (air sacs) open. Premature babies may not have enough surfactant in their lungs and may have difficulty breathing.